Apparatus for Treating Malformative and Traumatic Conditions Affecting the Knee Area

Abstract

An apparatus for treating malformative and traumatic conditions affecting the knee area, having an external fixation means for fixing bone portions together and first and second bone screws to be engaged respectively in the epiphyseal and diaphyseal region of the femur/tibia and to which the fixation means is to be coupled. The apparatus includes a guiding means, which is separate from the fixation means, for guiding the surgeon in the operations for identifying a plurality of drilling points on these regions, for producing engagement holes in these regions at the drilling points, and for inserting the bone screws in the engagement holes. The separate provision of the guiding means allows to simplify the structure of the fixation means with respect to existing fixation means.

1 . An apparatus for treating malformative and traumatic conditions affecting the knee area, comprising an external fixation means for fixing bone portions together, first and second bone screws to be engaged respectively in the epiphyseal and diaphyseal regions of the femur/tibia, said fixation means being adapted to be coupled to said screws, further comprising a guiding means which is separate from said fixation means for guiding the surgeon in the operations for identifying a plurality of drilling points on said regions, for providing engagement holes in said regions at said drilling points, and for inserting said bone screws in said engagement holes. 
   
   
       2 . The apparatus according to  claim 1 , wherein said fixation means also comprises a first supporting body, a first coupling means for coupling said first supporting body to said first bone screws, an actuation body which is connected to said first supporting body, a second supporting body which is connected to said actuation body, and a second coupling means for coupling said second supporting body to said second bone screws. 
   
   
       3 . The apparatus according to  claim 2 , wherein said first supporting body comprises an annular member which partly accommodates said first coupling means, at least three through holes provided so as to be angularly equidistant in a radial direction on said annular member in order to accommodate respectively an extraction preventing screw, to prevent the extraction of said first coupling means from said annular member, and two first locking pins for locking together said first coupling means and said first supporting body, and an externally threaded wing which protrudes on a plane from the peripheral region of said annular member and is engaged by a screw coupling in said actuation body. 
   
   
       4 . The apparatus according to  claim 2 , wherein said first coupling means comprises a transverse pivot which is inserted in said annular member and engages said first bone screws, two spacers arranged proximate to the ends of said transverse pivot, and two lock nuts for locking said first bone screws to said transverse pivot which are engaged at the ends of said transverse pivot. 
   
   
       5 . The apparatus according to  claim 4 , wherein said transverse pivot comprises a central region for the engagement of said extraction prevention screw and of said first locking pins, two through holes provided at the sides of said central region for the insertion of said first bone screws, and threaded terminal portions for coupling to said lock nuts. 
   
   
       6 . The apparatus according to  claim 2 , wherein said actuation body comprises a sleeve member, which is partially accommodated within said second supporting body and in turn accommodates partially said first supporting body. 
   
   
       7 . The apparatus according to  claim 6 , wherein said sleeve member externally comprises a first portion, which forms an engagement seat for engaging an actuation tool, two through holes provided at said seat in a diametrically opposite condition in order to accommodate two second locking pins for locking together said actuation body and said first supporting body, a second portion provided with a first thread for coupling to said second supporting body, and internally a second thread for coupling to said first supporting body, said second thread being provided in the opposite direction with respect to said first thread. 
   
   
       8 . The apparatus according to  claim 6 , wherein said second supporting body comprises a tubular portion, which partially accommodates said sleeve member, and a bar portion, which supports said second coupling means. 
   
   
       9 . The apparatus according to  claim 8 , wherein said tubular portion comprises an internal thread for coupling to said first thread, which is formed on said sleeve member, and two through holes provided in a diametrically opposite condition in the collar of said tubular portion in order to accommodate two third locking pins in order to lock together said second supporting body and said actuation body. 
   
   
       10 . The apparatus according to  claim 8 , wherein said bar portion comprises, in the central region, an elongated slot for accommodating said second coupling means. 
   
   
       11 . The apparatus according to  claim 10 , wherein said second coupling means comprises engagement pivots for engaging said second bone screws that are inserted in said slot, through holes for the insertion of said second bone screws, said through holes being provided proximate to first ends of said pivots, plate members fitted on said pivots at either end of said bar portion, nuts for locking said pins and engaged at the second end of said engagement pivots in order to simultaneously lock said bone screws to said coupling means and said coupling means to said bar portion. 
   
   
       12 . The apparatus according to  claim 1 , wherein said guiding means comprises an elongated body to be arranged along the longitudinal axis of said femur/tibia with a first terminal portion and a second terminal portion to be superimposed respectively on said epiphyseal region and on said diaphyseal region of said femur/tibia, two first guiding holes and two second guiding holes for guiding said surgeon in said operations for identifying said drilling points, for producing said engagement holes and for inserting said bone screws respectively in said epiphyseal region and in said diaphyseal region of said femur/tibia. 
   
   
       13 . The apparatus according to  claim 12 , wherein said guiding means comprises a passage hole for passing a guiding wire which is inserted in the region of said knee, said hole being provided proximate to the end of said first terminal portion. 
   
   
       14 . The apparatus according to  claim 13 , wherein said first guiding holes are provided in said terminal portion in a region which is adjacent to said passage hole and are aligned transversely to the longitudinal axis of said body, said second guiding holes being provided in said second terminal portion and being aligned in a longitudinal direction. 
   
   
       15 . The apparatus according to  claim 12 , wherein said first and second terminal portions lie on offset planes. 
   
   
       16 . The apparatus according to  claim 13 , wherein said passage hole and said pairs of first and second guiding holes partially accommodate tubular bodies to facilitate the guiding of drilling bits and of said screws.